It hasn’t, yet, afaict. Applying for a patent != it being granted.
As to the latent question of why Microsoft seems confident enough to try:
Because the times of a patent requiring to clear a reasonable inventive threshold (to actually be a motor for innovation) are far behind us. These days, patents’ principal (not exclusive) purpose imho is so big corporations can sue each other to grab some of the others’ earnings.
It hasn’t, yet, afaict. Applying for a patent != it being granted.
As to the latent question of why Microsoft seems confident enough to try:
Because the times of a patent requiring to clear a reasonable inventive threshold (to actually be a motor for innovation) are far behind us. These days, patents’ principal (not exclusive) purpose imho is so big corporations can sue each other to grab some of the others’ earnings.